The present invention relates to means for testing electrical circuits to determine in which of a plurality of pre-wired circuits a particular outlet or other circuit point is connected, and/or to determine whether there is electrical continuity between a pair of conductors.
In the service wiring of virtually any modern commercial or residential building, an incoming AC power line is connected to a fuse box or other circuit breaking means for protection in the event a circuit is loaded beyond a desired amperage. Normally the structure is wired with a plurality of separate, electrically distinct circuits each connected to a different fuse or circuit breaker. Each circuit may, and commonly does, include a number of receptacles or other outlets for selectively connecting the items to receive electrical power from the circuit.
Many situations arise which make it necessary to determine in which circuit a particular outlet is connected, where this is not otherwise indicated. This can be a very time-consuming operation, especially when it must be performed by one person working alone. In many cases the fuse box or circuit breakers will be located at a considerable distance from the outlet of the circuit being traced, often on a different floor of the building. Many trips back and forth between the outlet and fuse/breaker box may be required before the proper circuit is identified.
Another common situation which arises, for example, during wiring operations in building and elsewhere, is the need to determine whether two conductors are electrically connected. That is, it must be determined whether circuit continuity exists between two conductors where no external power is being provided thereto.
It is an object of the present invention to provide novel and improved apparatus for determining in which of a plurality discrete electrical circuits a particular electrical outlet is connected.
A further object is to provide a circuit tracing apparatus for connection to an existing outlet which will provide an audible indication to an operator at a remote location when electrical power is supplied to said outlet, when operated in a first mode, or when power is removed when operated in a second mode.
Another object is to provide circuit testing apparatus capable of providing an indication of which of a plurality of discrete circuits incorporate a particular outlet or other circuit point, and also of whether circuit continuity exists between two unpowered conductors.
A still further object is to provide circuit tracing apparatus operable in the two above-mentioned modes which may be employed with either AC or DC circuits, each at a plurality of voltage levels.
Still another object is to provide circuit tracing apparatus operable in the two above-mentioned modes which incorporates radio transmitting and receiving means to actuate an audible signal.
Still another object is to provide apparatus of the character described which is small, lightweight, portable, inexpensive and simple in both construction and operation.
Other objects will in part be obvious and will in part appear hereinafter.